package com.diao.netty;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.util.CharsetUtil;
import io.netty.util.concurrent.EventExecutorGroup;

/**
 * @author: chenzhidiao
 * @date: 2021/4/18 12:20
 * @description:
 * @version: 1.0
 */
public class NettyClientHandler extends ChannelInboundHandlerAdapter {
    /**
     * 当通道就绪时就会触发该方法执行
     * @param ctx
     * @throws Exception
     */
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("client ctx =" + ctx);

        ctx.writeAndFlush(Unpooled.copiedBuffer("Hello服务端", CharsetUtil.UTF_8));

        System.out.println("客户端发送请求完毕");
    }

    /**
     * 读取数据的方法，当通道有读取事件时会触发
     * @param ctx
     * @param msg
     * @throws Exception
     */
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {

        ByteBuf buf = (ByteBuf) msg;

        System.out.println("服务端返回的消息为：" + buf.toString(CharsetUtil.UTF_8));

        System.out.println("服务器端地址为：" + ctx.channel().remoteAddress());
    }

    /**
     * 异常处理
     * @param ctx
     * @param cause
     * @throws Exception
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();
        ctx.close();
    }
}
